Two men and a woman were arrested by the police on Wednesday evening after a drug raid, the police said.
Members of the Police Drug Squad and others from the Rapid Intervention Unit arrested the men, aged 39 of Paola and 56 of Marsascala.
The men were found in possession of 600 grammes of cannabis resin. The police did not say where the arrests took place.
Later, a woman, also of Marsascala, was also arrested.
Magistrate Donatella Frendo Dimech is leading an inquiry.